Double Layer Graphene Turns Into Supertough Material When Under Impact

Graphene, an incredibly strong material made up of a single layer of carbon atoms joined in a honeycomb pattern, is pretty darn versatile. As time goes by, more and more new possible applications of the supermaterial are being discovered.

The Advanced Science Research Center (ASRC) at the Graduate Center, CUNY, concocted a new type of double graphene sheet, each layer being one-atom thick. They have theorized that it could be made to transform into a diamond-like material upon impact at room temperature. The same team also found the moment of conversion resulted in a sudden reduction of electric current, suggesting “diamene” (the name used in reference to double-layer graphene) could have interesting electronic and spintronic attributes.

“This is the thinnest film with the stiffness and hardness of diamond ever created,” said Elisa Riedo, professor of physics at the ASRC and the project’s lead researcher. “Previously, when we tested graphite or a single atomic layer of graphene, we would apply pressure and feel a very soft film. But when the graphite film was exactly two-layers thick, all of a sudden we realized that the material under pressure was becoming extremely hard and as stiff, or stiffer, than bulk diamond.”

The team leader Riedo and other members then used an atomic force microscope to apply localized pressure to two-layer graphene on silicon carbide substrates and found perfect agreement with their hypothesis. Practice and calculations now both prove that graphite-diamond transition does not occur for more than two layers or for a single layer.

“Graphite and diamonds are both made entirely of carbon, but the atoms are arranged differently in each material, giving them distinct properties such as hardness, flexibility and electrical conduction,” Bongiorno said. “Our new technique allows us to manipulate graphite so that it can take on the beneficial properties of a diamond under specific conditions.”